I have both, a hardie and an heirloom and the wool used in the hardie is much softer than that of the heirloom. The heirloom is much warmer I find though.Edit: I also find that the hardie has a tighter weave to it, with less stretch than the heirloom. On the other hand the heirloom is also considerably heavier. The hardie is really nice but I do prefer the heirloom. Especially since the heirloom is so much cheaper.